* build-globals.sh
- Only look in the nuttx for external symbols used when loading
dynamic shared objects
* include/elf64.h
- Correct the type of fields in the Elf64_Phdr structure
* libs/libc/dlfcn/lib_dlclose.c
- Distinguish between ET_DYN and other objects as the former
has both text and data in a single allocation to reserve
GOT offsets
* libs/libc/dlfcn/lib_dlopen.c
- Code formatting
* libs/libc/modlib/modlib_bind.c
- Distinguish between relocation entry sizes by section type
- Handle RELA style relocations
* libs/libc/modlib/modlib_globals.S
- Formatting fixes
- Symbols should not be weak - they exist or they don't
* include/nuttx/lib/modlib.h
- Add an inidcator to module_s to distinguish between ET_DYN and other
* libs/libc/modlib/modlib_load.c
- ET_DYN objects need to keep the relative displacement between the text
and data sections due to GOT references from the former to the latter.
This also implies that linking may require modification from the default
for the shared objects being produced. For example, default alignment may
mean nearly 64K of wasted space.
* libs/libc/modlib/modlib_unload.c
sched/module/mod_rmmod.c
- Distingusih between freeing of ET_DYN storage and other as the former
is a single allocation.
* libs/libc/modlib/mod_insmod.c
- Cater for ET_DYN objects having init and preinit sections
* libs/libc/machine/arm/armv7-m/arch_elf.c
- Fix cast of error message parameters
* build-globals.sh
- Build the modlib_globals.S file used to resolve symbols when dynamically loading
* libs/libc/modlib/Make.defs
- Build modlib_globals.S for all targets
* libs/libc/modlib/modlib_load.c
- Calculate sizes and text/data addresses based on program headers rather than section headers
- Handle objects with no program headers
* libs/libc/modlib/modlib_bind.c
- Call modlib_readsym with pointer to symbol table
- Add modlib_relocatedyn to manage relocation of symbols with shared object (ET_DYN)
- Differentiate between ET_REL and ET_DYN objects
- Use arch independent symbol ELF_R_SYM
- Cast sizes to avoid warnings
* libs/libc/modlib/modlib_load.c
- Cast sizes to avoid warnings
* include/elf.h
- Add definitions that may be found in shared objects
* include/nuttx/lib/modlib.h
- Add parameter to modlib_readsym prototype
- Add prototypes for:
- modlib_insertsymtab
- modlib_findglobal
- Define Elf_Dyn and Elf_Off according to the elf architecture
- Add fields to mod_loadifno_s:
- Program headers
- Exported symbols
- Data section address
- Padding requirement
- Section index for dynamic symbol table
- Number of symbols exported
- Add prottotype for modlib_freesymtab
* libs/libc/dlfcn/lib_dlclose.c
- Free the symbol table when the dll is closed
* libs/libc/dlfcn/lib_dlopen.c
- Add dump of program headers to debug routine
- Differentiate between ET_REL and ET_DYN objects
* libs/libc/machine/arm/armv7-m/arch_elf.c
- Add handling of R_ARM_RELATIVE and R_ARM_JUMP slot relocation types
* libs/libc/modlib/modlib_loadshdrs.c
- Rename modlib_loadshdrs.c to modlib_loadhdrs.c
- Rename modlib_loadshdrs to modlib_loadhdrs
- Add code to load program headers
* libs/libc/modlib/modlib_symbols.c
- Define entry point structure
- Add offset parameter to modlib_symname() and use to find symbol names
- Add symtab section header parameter to modlib_readsym()
- Add offset parameter to modlib_symvalue() to locate symbol names
- Add modlib_insertsyntab() to create a symbol table for exporting and resolution
- Add findEP() to resolve a symbol in the modlib_global table
- Add modlib_findglobal() to find symbol in the modlib_global table
- Add modlib_freesymtab() to free the symbol table
* libs/libc/modlib/modlib_uninit.c
- Free header and sections from a module_loadinfo_s control block
* libs/libc/modlib/modlib_verify.c
- Handle ET_DYN shared objects
* libs/libc/modlib/modlib_globals.S
- Multi-target global table
- Define library APIs that may be resolved when loading a shared object
Pros:
* Reduce code differences
* Smaller allocations for !CONFIG_ARCH_USE_MODULE_TEXT
Cons:
* Likely to use more memory for !CONFIG_ARCH_USE_MODULE_TEXT in total
Tested with:
* sim:module on macOS
* esp32-devkit:nsh + CONFIG_MODULE on qemu
* lm3s6965-ek:qemu-protected + CONFIG_EXAMPLES_SOTEST on qemu
* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro